Isolated human peripheral lymphocytes were treated in vitro with styrene-7, 8-oxide (SO) and the kinetics of the repair of induced DNA damage was assessed by comet assay during further incubation of lymphocytes. Using a modified assay we measured simultaneously the number of single strand breaks in DNA (SSBs) and the sites sensitive to endonuclease III (endo III) that most probably represent abasic sites in DNA molecules. SO induced DNA damage in a dose-dependent manner and both SSBs and endo III sites were removed from the DNA by a repair process with a half time about 2-4 hours. The damage was repaired completely within 12 hours after the treatment.

• MeSH
• epoxidové sloučeniny toxicita   MeSH
• kometový test MeSH
• kultivované buňky MeSH
• lidé MeSH
• lymfocyty účinky léků   metabolismus   MeSH
• mutageny toxicita   MeSH
• oprava DNA * MeSH
• poškození DNA účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• epoxidové sloučeniny MeSH
• mutageny MeSH
• styrene oxide MeSH Prohlížeč

Platinum-based chemotherapeutic agents induce the formation of crosslinks in DNA, which are accepted as being responsible for the cytotoxicity of these agents. In this study, we used a modification of the alkaline comet assay for detection of the presence of DNA crosslinks in vitro caused by cisplatin, and in peripheral lymphocytes of patients with non-small cell lung carcinoma undergoing chemotherapy with platinum derivatives. The comet technique modified for the detection of DNA crosslinks was calibrated in vitro by treating HeLa cells and human lymphocytes from healthy donors with different concentrations of cisplatin. A cisplatin dose-dependent formation of DNA crosslinks was observed in in vitro measurements using 10-200 µM concentrations of cisplatin. Lymphocytes from cancer patients were also assayed for the formation and repair of DNA crosslinks. Evidence of crosslink formation and repair was observed in peripheral blood lymphocytes of all cancer patients in this study, although some inter-individual differences were observed in the response to chemotherapy and in repair of DNA crosslinks. We propose that monitoring the number of DNA crosslinks in peripheral blood lymphocytes might be a quick and sensitive method for monitoring a patient's sensitivity to this agent. Modification of the method by incubation of analysed cells with styrene oxide before crosslink analysis by comet assay extends the use of the method also to laboratories which have no facilities to use ionizing irradiation for introducing DNA breaks into the cells.

• MeSH
• cisplatina farmakologie   MeSH
• HeLa buňky MeSH
• kometový test metody   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lymfocyty účinky léků   metabolismus   MeSH
• nádory plic farmakoterapie   genetika   MeSH
• nemalobuněčný karcinom plic farmakoterapie   genetika   MeSH
• poškození DNA * MeSH
• protinádorové látky farmakologie   MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cisplatina MeSH
• protinádorové látky MeSH